Find the solutions to the following linear-quadratic systems algebraically. Select the ordered pair that is one of the correct solutions from among the choices below.
y = x² +3x + 8
y = 2x + 10

(-2, 6)
(0, 8)
(0,10)
(2, 14)

Answer :

calculista

Answer:

(-2, 6)

Step-by-step explanation:

we have

[tex]y=x^{2} +3x+8[/tex] ----> equation A

[tex]y=2x+10[/tex] ----> equation B

equate equation A and equation B

[tex]x^{2} +3x+8=2x+10[/tex]

[tex]x^{2} +3x+8-2x-10=0[/tex]

[tex]x^{2} +x-2=0[/tex]

The formula to solve a quadratic equation of the form

[tex]ax^{2} +bx+c=0[/tex]

is equal to

[tex]x=\frac{-b\pm\sqrt{b^{2}-4ac}} {2a}[/tex]

in this problem we have

[tex]x^{2} +x-2=0[/tex]

so

[tex]a=1\\b=1\\c=-2[/tex]

substitute in the formula

[tex]x=\frac{-1\pm\sqrt{1^{2}-4(1)(-2)}} {2(1)}[/tex]

[tex]x=\frac{-1\pm\sqrt{9}} {2}[/tex]

[tex]x=\frac{-1\pm3} {2}[/tex]

[tex]x=\frac{-1+3} {2}=1[/tex]

[tex]x=\frac{-1-3} {2}=-2[/tex]

Find the values of y

For x=1

[tex]y=2(1)+10=12[/tex]

For x=-2

[tex]y=2(-2)+10=6[/tex]

therefore

The solutions are (1,12) and (-2,6)

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